The overall goal of this Phase II STTR proposal is to develop a PET/CT imaging tool that will help accelerate the development of effective cancer therapies by improving the utility of oncology trials using PET imaging. The growing cost, time, and complexity of clinical trials are driving patient and pharmaceutical company demand for more objective, efficient, and accurate methods to assess the efficacy of therapeutic agents. PET/CT imaging has the potential to provide a quantitative and early assessment of drug response at a molecular level However, PET/CT use as a biomarker and response endpoint in clinical trials is limited. Key factors impeding the incorporation of PET into clinical trials are:the considerable variability in imaging methods across centers, the inconsistency in quantitative measures arising from different sites, and the variable and non-optimal methods for image analysis. In our Phase I work, we developed calibrated quantitative analysis tools that directly support improved quantitative accuracy in clinical trials using PET/CT imaging. We combined the CT 'pocket phantom', developed by Kitware, with a PET scanner calibration process developed at the University of Washington (UW) that is based on National Institute of Standards and Technology (NIST) traceable calibration sources. We also extended our automated algorithms to detect and measure the phantom, and calculate key PET image characteristics. The Phase I proof-of concept study achieved its specific aims, and in this Phase II submission, we will develop and implement the studies and tools needed to translate our proof-of-concept results to use with human imaging for clinical trials. The end goal of the phase II project is to complete all necessary work to market PET/CT calibration and measurement phantoms and analysis services.